Updated: Two commercial shrimpers have filed a federal lawsuit in Louisiana against the owner and operator of a oil rig that exploded and sank last week in the Gulf of Mexico, resulting in a massive oil leak, and similar actions are being filed in federal court in other states, too.

Meanwhile, the Wall Street Journal (sub. req.) reports that experts say the undersea well could be leaking as much as 25,000 barrels daily. That is five times the current government estimate that led to reports that damage from the Gulf spill likely would dwarf the 1989 Exxon Valdez disaster in Alaska.

Why both a blowout preventer and a back-up system failed to prevent the leak “is a mystery, a huge Apollo 13-type mystery,” an unidentified source tells the New York Times.

So far, despite 24/7 brainstorming, dozens of engineers and technicians working in Houston haven’t been able to figure out a way to stop the gush.

The suit seeks to represent all injured Louisiana residents in a class action against British Petroleum and Transocean Ltd., CBS News reports.

It also names as defendants Halliburton Energy Services Inc., which is accused of improperly sealing the well and its cap with cement, and Cameron International Corp., which supplied the blowout preventers.

Kennedy & Madonna is one of the law firms representing the plaintiffs, Acy Cooper Jr., and Ronnie Louis Anderson, in the Eastern District of Louisiana complaint (PDF). It asserts claims for negligence and damages under the Oil Pollution Act.

After earlier reporting that the Huey Law Firm had filed a similar federal class action on behalf of Alabama residents, WALA is now saying that Cunningham Bounds has filed suits on behalf of various parties allegedly harmed by the leak.

The Associated Press reports that a Mississippi seafood company has filed a federal class action there.